Impregnation of textile materials by latex



June 4, 1935. J. E. c. BONGRAND ET m. 2,004,629

IMPREGNATION OF TEXTILE MATERIALS BY LATEX Filed Oct 28, 1932 emu Fig.1

Patented June 4, 1935 UNITED .STATES PATENT OFFlCE IMrnEGNATIoN F rnxmnMATERIALS Br LATEX Jean Etienne Charles Bongrand, Paris, and LeonSylvain Max Lejeune, Wasquehal, France Application 9 Claims.

This invention consi ts of improvements inor relating to theimprefiEtion of extile materials by latex.

The expression textile materials" is used to include fibres, rovings,slivers, yarns, threads,

cords-felts, tissues and fabrics.

It is -known that in order to impregnate textile materials with liquidrubber latex or any aqueous dispersion prepared from natural coagulatedrubber, artificial rubber or regenerated rubber, immersion is employedand sometimes recourse is had to mechanical aids such as the applicationof vacuum and of pressure. Reference may bemade to U. S. Patents Nos.1,959,723, dated May.

22, 1934, and 1,964,658, dated June 26, 1934.

Again it has already been proposed to facilitate the impregnation bypretreatment of the fibres or of the latex (including the addition ofwetting or peptising agents or the'like to the latex). Reference may bemade to the specification of our concurrent application No. 640,126,filed Oct. 28, 1932.

This invention comprises a process for facilitating the impregnation oftextile materials 'by latex in which after impregnation the textilematerials are maintained in a humid atmosphere containing vapours of ananti-coagulating agent and the textile materials in the form of bobbins,I

rolls or the like are caused to turn or rotate slowly. Preferably, theatmosphere in which the textile materials are maintained is charged withmoisture and with ammonia. The process which is in the nature of amaturing or ripening operation may be continued for hours and has theeflect of increasing the penetration of the latex into the fibresand'therefore increasing the quantity of rubber fixed in said fibres. I

By the terms "ripening or maturing operation, as used in thisspecification, is meant the process of maintaining a textile materialimpregnated with an aqueous rubber dispersion in an atmosphere in whichevaporation of moisture can only take place slowly and in whichcoagulation of the rubber is prevented in order that completeimpregnation of the fibres of the textile material may be effected, theimpregnation being accompanied by an increase in the viscosity of thelatex.

During the maturing period, the

liquid latex fibres before maturing have been superficially impregnated,deep impregnation may be ensured; the latex is'maintained in a liquidstate and after a period which varies according to the nature ofcontinues to penetrate into the fibres and .where the textile materialthe latex succeeds in wetting October 28, 1932, Serial No. 640,128 InFrance July 19, 1932 and penetrating each of the fibrils. On proceed-'-ing subsequently to coagulation, each of these fibrils will bepenetrated and surrounded by coagulated rubber.

This process is preferably carried out in con- (1) It is essential toavoid coagulation of the latex through drying or other cause.

(2) Draining of the latex away from textile material 'must be avoided.

The first condition is satisfied by allowing the impregnated materialsto remain in a chamber the atmosphere of which is very moist and -ischarged with an anti-coagulant, such as ammoniacal vapours. The humidityof the atmosphere prevents the drying of the latex and theanti-coagulating agent prevents coagulation, (owing for example to thecarbon dioxide of the air) and has a definite retarding effect on thecoagulation. I

The second condition is satisfied by a turning movement of the bobbinsor rolls of textile material. For example, the bobbins may be arrangedwith their axes horizontal on the vertical face of a disc slowlyrotating on a horizontal axis. The effect of the slow turning of thebobbins of impregnated textile materials is to prevent the draining ofthe liquid latex away from the ma-. terial. The maturing operation maybe prolonged as longas is necessary to ensure the complete penetrationof the fibres. The accompanying drawing represents dia grammatically andby way of example the arrangement of .a ripening installation accordingto the present invention. 4

- In this drawing Figure 1 is a view in elevation of the installation.

Figure 2 is a view in plan thereof.

Figure 3 is an end view thereof. a

As represented in the drawing, the installation comprises a pump I whichdraws water from. a tank 2. This water is led through the conduit 3 andis evaporated by the humidifiers 4 situated in the upper part of theroom 5. The excess of water returns to the tank through the pipe 6.

A hygrometer enables the degree of humidit .to be watched and regulated.

The water of the tank 2 may be ammoniacal or may contain any suitableproduct which, when vaporized, will retard the coagulation or the rub-55 her. If the bath with which the textiles have been impregnated isrich in ammonia, pure water alone may be evaporated in the room.

Maturing wheels l l T W, are disposed on one shaft 8 rotating at a lowspeed, for example, about four revolutions per minute.

The bobbins 9 of impregnated textile materials are disposed on spindlesl fixed to the two faces of each wheel.

The ripening room is kept closed and at a temperature of 15 to 20 C. Theimpregnation latex cannot coagulate in this atmosphere.

The movement of the wheels l l 7, li causes the drops of liquid. whichwould have a tendency to run off the bobbins under the influence ofgravity, to be reabsorbed by the textile and the impregnation which hasthus been initiated may be extended for several days if necessary.

Microscopic and ultra-microscopic examination of the textile fibres haveproved that, after such ripening, the impregnation by liquid rubberlatex was much deeper than without this ripening.

We claim:

1. A process for facilitating the complete impregnation of textilematerial with rubber which comprises treating the said textile materialwound in the form of bobbins with rubber latex and subsequentlymaintaining the textile material while still wet with the rubber latexin a humid atmosphere containing vapors of an anti-coagulating agent,the excess of latex being retained in contact with the said textilematerial by the slow rotation of said bobbins.

2. A process for facilitating the complete impregnation of textilematerial with rubber which comprises treating the said textile materialwound in the form of bobbins with rubber latex and subsequentlymaintaining the textile material while still wet with the rubber latexin an atmosphere charged with moisture and with ammonia, excess of latexbeing retained in contact with the textile material by slow rotation ofsaid bobbins.

3. A process for the maturing of latex-impregnated textile materialswhich consists in moving the said impregnated textile material whilestill wet with the impregnating liquid 'slowly in a humid atmospherecontaining vapors of a volatile anti-coagulating agent, therebypreventing liquid from dropping from the textile rfiaterial.

4. A process for the maturing of latex-impregnated textile materialswhich consists in moving the said impregnated material while still wetwith the impregnating liquid slowly in a humid atmosphere containingammonia, thereby preventing liquid from draining from the textilematerial.

5. A process for the maturing of latex-impregnated textile materialswhich consists in moving the impregnated material while wound in theform of bobbins and while still wet with the impregnating liquid slowlyin a humid atmosphere containing ammonia vapor, thereby preventingliquid from draining from the textile material.

6. A process for the maturing of latex-impregnated textile materialswhile wound in the form of bobbins which consists in moving the bobbinswhile still wet with the impregnating liquid slowly in an atmospherecharged with moisture and with ammonia vapor, thereby retaining theexcess of rubber latex in contact with said textile material.

7. A process for the maturing of latex-impregnated textile materialswound on bobbins which consists in moving the bobbins while still wetwith the impregnating liquid in a humid atmosphere containing ammonia,excess of latex being retained in contact with the textilematerial byslow rotation of said bobbins. v

8. A process for the maturing of latex-impregnated textile materialswound on bobbins which consists in rotating the bobbins while still wetwith the impregnating liquid slowly upon their axes in a closed. chambercontaining a humid atmosphere and charged with ammonia vapor so as toprevent liquid from draining from the textile material.

9. A process for the maturing of latex-impregnated textile materialswound on bobbins which consists in turning the bobbins while still wetwith the impregnating liquid in a closed vessel maintained at atemperature between 15 and 20 C. and containing a humid atmosphere andammonia vapor so as to prevent latex from draining from the bobbins.

J EjAN ETIENNE CHARLES BONGRAND. LEON .SYLVAIN MAX LEJEUNE.

